In recent years, a growing number of vehicles have been equipped with a lighted switch device, disposed on a front panel in a vehicle interior, with various styles of operators to operate various kinds of electronic equipment such as air-conditioner or audio equipment. Japanese Patent Unexamined Publication No. 2005-216798 discloses such a lighted switch device.
A conventional switch device and an input device using the same are described with reference to FIGS. 4 and 5. FIG. 4 shows a cross-sectional view of the conventional switch device and the input device using the same, and FIG. 5 shows an exploded perspective view of the conventional switch device and the input device using the same. The input device using the conventional switch device includes a substantially disk-shaped operator 210 formed from an insulating resin and indications 220 as shown in FIGS. 4 and 5. On the top surface of operator 210, indications 220 are applied by laser machining, co-injection molding or the like so as to expose predetermined forms of characters, symbols, figures or the like on a transparent or light colored translucent portion 212 surrounded by opaque portion 211 colored in black or the like.
Switch-element 230 with an upward projecting operation axis 231 includes a plurality of contacts (not shown) internally to perform electrical switching by rotating or vertical moving of operation axis 231. Operation axis 231 is fixed into cylindrical projection 213 projecting from the bottom surface of operator 210.
Wiring board 240 having a plurality of wiring patterns (not shown) on its top and bottom surfaces and substantially box-shaped case 250 formed from an insulating resin form the switch device. Case 250 covers switch-element 230 and light emitting elements 260 such as light emitting diodes mounted on the top surface of wiring board 240, and operator 210 projects rotatably and movably vertically out of cylindrical opening 251 formed in the center of case 250.
Controller 270 is formed on the top surface of wiring board 240 using electronic components such as micro-computers. Switch-element 230 and light emitting elements 260 are connected to controller 270 via the wiring patterns to form a conventional input device.
Such a conventional input device has been installed on the front panel or the like in a vehicle interior and controller 270 is connected electrically to various kinds of electronic equipment such as an air-conditioner or audio equipment and vehicle electronic circuits (not shown) via connectors or lead wires (not shown).
In the above configuration, upon rotating operator 210 clockwise or counter-clockwise, operation axis 231 fixed on the bottom surface of operator 210 rotates together to perform electrical switching of contacts in switch-element 230, thereby transmitting the signals from controller 270 to electronic devices or electronic circuits to control for instance the air-conditioning temperature.
Upon pressing operator 210 downward, operation axis 231 is pressed to perform electrical switching of contacts in switch-element 230, thereby changing the temperature setting mode for air-conditioning from automatic to manual.
Moreover, light emitting elements 260 turn on in a case when it is dark such as at night to illuminate operator 210 from below. Since the light past translucent portion 212 illuminates indications 220 on the upper surface, characters, symbols, figures or the like on indications 220 become visible so that operator 210 can be identified and operated easily even in the case when it is dark.
Namely, the switch device can operate various functions of electronic equipment such as an air-conditioner by rotating or pressing downward operator 210 and can perform the operation easily with the aid of illuminated indications 220 on operator 210 even when it is dark.
As described above, however, since indications 220 in characters, symbols, figures or the like are formed integrally on the top surface of operator 210 in the input device using the conventional switch device, indications 220 rotate together with the rotation of operator 210, causing the indications to turn sideways or upside down. The problem is, therefore, that it is difficult for a driver to view the indications until he/she becomes accustomed to the operation, which can cause operational errors.